And yes its your build but why join and make a thread if you already know what you wanna do ?

And if you so concern about how many fps your getting go for it

Imo I don't even look at fps if I'm gaming and everything is max out and I'm not lagging I'm good

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yes. also i might just keep one.
res is 1080x1980.
i just remember my other gpu i had was an 6990 XFX and i sold it because of the microstuttering... it was to anoying for me.
no but srsly everything under 50 - 55 is stuttering for me. like lagging. even 30 fps is lagging like hell. i rly need a 60 fps or above always.
im just aiming at ArmA 3 since i loved the second one and dayz sa ofcourse. i just wanted you guys opinions.
its just ive seen so many builds / sli without 120Hz screens.
and the upcoming games...

Yes it will be enough but your load will be too high so your PSU will die very prematurely. You will also have a heat problem. I suggest upgrading to an HX750 Gold. I believe the TX is only bronze. I just saw the HX750 go for $70 on newegg yesterday. I know for a fact that it is a seasonic rebrand by corsair. CORSAIR HX Series HX750 750W ATX12V 2.3 / EPS12V 2...

Too bad it is $150 now but it maintains its 5 eggs ratings even after 832 reviews is impressive for any product.

Hard headed people are hard headed.. So, you are willing to add another GTX680 to your system, and not buy a new psu to handle the load. You come to TPU, and quote what other people said in other forums, and totally disregard what everybody at TPU has told you.. I'll give you some advice.. Listening to other people and not the manufacturer, is not a wise decision.. That psu isn't even rated for SLi.. of any kind.. It's a 650w bronze series powersupply.. The maximum load on a stock GTX680 is 195w and the Minimum is a 550w PSU for a single GTX680..

Let me explain it a little better.. If you add another GTX680 to your system, and your PSU fails, and takes out your computer what then? are you going to go back to that forum, and post, "It didn't work?". Will those people buy you new parts for a new computer? or laugh and say, "Oh well".. I can understand that you have the money for a GTX680 now and not a new PSU.. So, buy it, and don't use it until you get a better PSU.

I can guarantee you one thing if you don't listen to everyone telling you to get a PSU.. And your system fails you can come back to TPU, and we will help you find the best parts for your new system. I just wouldn't risk over 1k worth of video cards on an $89 dollar PSU.

Hard headed people are hard headed.. So, you are willing to add another GTX680 to your system, and not buy a new psu to handle the load. You come to TPU, and quote what other people said in other forums, and totally disregard what everybody at TPU has told you.. I'll give you some advice.. Listening to other people and not the manufacturer, is not a wise decision.. That psu isn't even rated for SLi.. of any kind.. It's a 650w bronze series powersupply.. The maximum load on a stock GTX680 is 195w and the Minimum is a 550w PSU for a single GTX680..

Let me explain it a little better.. If you add another GTX680 to your system, and your PSU fails, and takes out your computer what then? are you going to go back to that forum, and post, "It didn't work?". Will those people buy you new parts for a new computer? or laugh and say, "Oh well".. I can understand that you have the money for a GTX680 now and not a new PSU.. So, buy it, and don't use it until you get a better PSU.

I can guarantee you one thing if you don't listen to everyone telling you to get a PSU.. And your system fails you can come back to TPU, and we will help you find the best parts for your new system. I just wouldn't risk over 1k worth of video cards on an $89 dollar PSU.

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^^yep like he said. I would get at least a Gold PSU at 750w minimum if you run 680 SLI. The recommendation is 850W gold or platinum if you can afford it. Get a Seasonic or any Seasonic rebrand to be safe.
BTW you would probably want a modular PSU also with all that wiring you'll be running.

Its not just the wattage, its the quality also. Some manufactures load test there PSU in a refrigerated environment so the results are fubar.

icehotshot is a douche lol

You still have the issue of only two pci-e. I would never run a 680 off a adapter. I hate adapters. They didn't put 4 pci-e cords on there for a reason. Your trusting a $500 GPU to a $2 adapter

I got it, call Corsair and ask them. If they say yes put it in writing and they can pay for the card when it goes

But like I said it will work, its just close

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Jester I think your also saying how many AMPS the PSU has. All 650 watt PSU's do not have the same Amp rating on the rail(s). Always make sure the rail(s) have enough Amps. 2 x 7970 with a 3770K push about 720 watts on full load with the system and cards highly overclocked. 2 x 680's run less power so 650 watts will be close. As someone earlier stated, as long as he is not highly overclocked on CPU and GPU's, he will be fine but:

I use the rule not to push a PSU past 90% of its max output for long life. I would recommend a 750 Watt for 2 x 680's but you need to check the draw first.

Hard headed people are hard headed.. So, you are willing to add another GTX680 to your system, and not buy a new psu to handle the load. You come to TPU, and quote what other people said in other forums, and totally disregard what everybody at TPU has told you.. I'll give you some advice.. Listening to other people and not the manufacturer, is not a wise decision.. That psu isn't even rated for SLi.. of any kind.. It's a 650w bronze series powersupply.. The maximum load on a stock GTX680 is 195w and the Minimum is a 550w PSU for a single GTX680..

Let me explain it a little better.. If you add another GTX680 to your system, and your PSU fails, and takes out your computer what then? are you going to go back to that forum, and post, "It didn't work?". Will those people buy you new parts for a new computer? or laugh and say, "Oh well".. I can understand that you have the money for a GTX680 now and not a new PSU.. So, buy it, and don't use it until you get a better PSU.

I can guarantee you one thing if you don't listen to everyone telling you to get a PSU.. And your system fails you can come back to TPU, and we will help you find the best parts for your new system. I just wouldn't risk over 1k worth of video cards on an $89 dollar PSU.

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Relax mindweaver. He will be fine if he does not overclock for now. The guys is asking for advise and searching the internet. Help him.

Naviwinsgg, you can simply get a Watt -O- Meter and plug it into the wall when you install the cards. As you overclock CPU and GPU you can easily check the draw. If the system pulls over 620 watts, I would say get a larger PSU. If it pushes 590 watts like your guessing or so your good to go. There is a scientific measuring device he could use guys. At this point it is all conjecture how much his system will draw.

Jester I think your also saying how many AMPS the PSU has. All 650 watt PSU's do not have the same Amp rating on the rail(s). Always make sure the rail(s) have enough Amps. 2 x 7970 with a 3770K push about 720 watts on full load with the system and cards highly overclocked. 2 x 680's run less power so 650 watts will be close. As someone earlier stated, as long as he is not highly overclocked on CPU and GPU's, he will be fine but:

I use the rule not to push a PSU past 90% of its max output for long life. I would recommend a 750 Watt for 2 x 680's but you need to check the draw first.

Relax mindweaver. He will be fine if he does not overclock for now. The guys is asking for advise and searching the internet. Help him.

Naviwinsgg, you can simply get a Watt -O- Meter and plug it into the wall when you install the cards. As you overclock CPU and GPU you can easily check the draw. If the system pulls over 620 watts, I would say get a larger PSU. If it pushes 590 watts like your guessing or so your good to go. There is a scientific measuring device he could use guys. At this point it is all conjecture how much his system will draw.

he is arived now just in time. i apppreciate you guys for the replys.and info you give me.
most of the poeple say ill be fine included you without touching them ( overclocking , realy want to max them out but sadly i cant yet. ) i think i might just get a new psu next month or this month i'll see how it goes and let you guys know how it goes.. might just pump hem in right now or lil bit later in the afternoon , but on the other hand im still scared to put the second one in. as some poeple said above..

Jester I think your also saying how many AMPS the PSU has. All 650 watt PSU's do not have the same Amp rating on the rail(s). Always make sure the rail(s) have enough Amps. 2 x 7970 with a 3770K push about 720 watts on full load with the system and cards highly overclocked. 2 x 680's run less power so 650 watts will be close. As someone earlier stated, as long as he is not highly overclocked on CPU and GPU's, he will be fine but:

I use the rule not to push a PSU past 90% of its max output for long life. I would recommend a 750 Watt for 2 x 680's but you need to check the draw first.

Relax mindweaver. He will be fine if he does not overclock for now. The guys is asking for advise and searching the internet. Help him.

Naviwinsgg, you can simply get a Watt -O- Meter and plug it into the wall when you install the cards. As you overclock CPU and GPU you can easily check the draw. If the system pulls over 620 watts, I would say get a larger PSU. If it pushes 590 watts like your guessing or so your good to go. There is a scientific measuring device he could use guys. At this point it is all conjecture how much his system will draw.

Oh, I am relaxed buddy, and giving sound advice. So, let me get this straight, he should obtain a "scientific measuring device"?.. Because the people who build the PSU and doesn't rate it for SLi don't use "scientific measuring devices"? I believe putting that money toward a new rated PSU would be a better plan. Now I'll agree that it's possible for it to turn on and work, but for how long? a day? a week? hell maybe a year? and when that day is reached, and his PSU fails and takes his system with it then what?

Most none rated SLi and CF 650w powersupplies can handle turning on the system, but they have to be able to handle it for an extended period of time. You said your self that you don't like pushing a power supply, but you advice people to go ahead a do it they'll be fine? How about helping the guy and not telling him what he wants to hear.

he is arived now just in time. i apppreciate you guys for the replys.and info you give me.
most of the poeple say ill be fine included you without touching them ( overclocking , realy want to max them out but sadly i cant yet. ) i think i might just get a new psu next month or this month i'll see how it goes and let you guys know how it goes.. might just pump hem in right now or lil bit later in the afternoon , but on the other hand im still scared to put the second one in. as some poeple said above..

thanks everyone for the answers..

i'll surely get a new psu asap.

Naviwinsgg

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If your going to get a new PSU next month I'd wait.. I'm sure your current GTX680 can max out ArmA II. If your just worried about ArmA 3 then I'd wait until next month when you can buy a new PSU. Plus, when is ArmA 3 coming out? Surely not before you get a new PSU.

Oh, I am relaxed buddy, and giving sound advice. So, let me get this straight, he should obtain a "scientific measuring device"?.. Because the people who build the PSU and doesn't rate it for SLi don't use "scientific measuring devices"? I believe putting that money toward a new rated PSU would be a better plan. Now I'll agree that it's possible for it to turn on and work, but for how long? a day? a week? hell maybe a year? and when that day is reached, and his PSU fails and takes his system with it then what?

Most none rated SLi and CF 650w powersupplies can handle turning on the system, but they have to be able to handle it for an extended period of time. You said your self that you don't like pushing a power supply, but you advice people to go ahead a do it they'll be fine? How about helping the guy and not telling him what he wants to hear.

If your going to get a new PSU next month I'd wait.. I'm sure your current GTX680 can max out ArmA II. If your just worried about ArmA 3 then I'd wait until next month when you can buy a new PSU. Plus, when is ArmA 3 coming out? Surely not before you get a new PSU.

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yeah ill wait. ill get a new one maybe next week or even this week. dunno yet. i'll see how everything goes.

wich psu should i get for maximum overclocking on these beasts gpu's? 850?
cant wait to test these in some games...

A bit worrying that so many experienced members missed the point of the thread which was "Is my 650w power supply enough for my system If I add a second GTX 680?"

He never once asked if a second 680 was a waste of money for 1080p gaming?

Mindweaver has the right idea, better to wait it out and get the right PSU for the setup. A good high quality 650w and above offering should give you that piece of mind when adding that second card + overclocking. Good luck.

yeah ill wait. ill get a new one maybe next week or even this week. dunno yet. i'll see how everything goes.

wich psu should i get for maximum overclocking on these beasts gpu's? 850?
cant wait to test these in some games...

my other 680 lightning here wont run away lol.

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Since they're already factory overclocked then I wouldn't get anything less than a 850, because your an overclocker. I'd need to know how much stuff you have connected to your psu (HDD, SSD, PCI, PCI-e, etc..).. If it was me.. I believe I would get a Corsair HX1050 and it's probably overkill, but I've had a PSU to fail and take most of my computer with it...

On a side note.. hehehe
I've noticed that some of the people that says it's ok run 7970's and says it uses more power then a GTX680. If you look at the specs for both cards a stock 7970 min PSU is 400w and the min for a GTX680 is 550w... A stock GTX680 base clock is 1006mhz and the base clock on your lighting is 1110mhz. That's more than the boost clock of 1058mhz on a stock GTX680. I love math! hehehe

You should be fine at 750W. A PSU is rated at output so a 750W should give you 750W to use and will draw more at the wall.

2 GTX 680 will have a maximum power draw of 556W in the worst case scenario with no overclock.

You have 53A on your 12V rail which equates to 636W. You have 80 watts for your mobo and some parts but you fall within the spec of your power supply. However, I do not recommend running this for extended periods of time. If you want to maximize efficiency, minimize heat, and maximize longevity on your PSU then try to keep it around 50%. A 750W-850W PSU will suit your needs. I think whether you go 750 or 850 depends entirely how big your wallet is or how long you want it to last.

Since they're already factory overclocked then I wouldn't get anything less than a 850, because your an overclocker. I'd need to know how much stuff you have connected to your psu (HDD, SSD, PCI, PCI-e, etc..).. If it was me.. I believe I would get a Corsair HX1050 and it's probably overkill, but I've had a PSU to fail and take most of my computer with it...

On a side note.. hehehe
I've noticed that some of the people that says it's ok run 7970's and says it uses more power then a GTX680. If you look at the specs for both cards a stock 7970 min PSU is 400w and the min for a GTX680 is 550w... A stock GTX680 base clock is 1006mhz and the base clock on your lighting is 1110mhz. That's more than the boost clock of 1058mhz on a stock GTX680. I love math! hehehe

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I cannot take the min power requirement seriously. I think some manufacturers account for people with really crappy PSU(low amp 12V lines). My 7850 came with a recommendation of 500w psu and I'm running a 430W without any problems.

Since they're already factory overclocked then I wouldn't get anything less than a 850, because your an overclocker. I'd need to know how much stuff you have connected to your psu (HDD, SSD, PCI, PCI-e, etc..).. If it was me.. I believe I would get a Corsair HX1050 and it's probably overkill, but I've had a PSU to fail and take most of my computer with it...

On a side note.. hehehe
I've noticed that some of the people that says it's ok run 7970's and says it uses more power then a GTX680. If you look at the specs for both cards a stock 7970 min PSU is 400w and the min for a GTX680 is 550w... A stock GTX680 base clock is 1006mhz and the base clock on your lighting is 1110mhz. That's more than the boost clock of 1058mhz on a stock GTX680. I love math! hehehe

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alright i have one HDD 1TB
SSD 126GB M4
One lightning atm.

i might go for an 850 Watt psu since 1000 is really an overkill but future proof i suppose.

i've heard two lightnings heavy overclocked pull alot of wattage out of you're psu, might go to the 750ish. is that true?
i'll overclock them with the "hacked" bios.

I cannot take the min power requirement seriously. I think some manufacturers account for people with really crappy PSU(low amp 12V lines). My 7850 came with a recommendation of 500w psu and I'm running a 430W without any problems.

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True, there are some high watt PSU's out there with shitty multi 12v rails. I have a lot of CX430 psu's in my crunching farm purely due to the fact it has a strong single 12v rail. But.. I believe I would follow the min requirements of the manufacture to not void my warranty. and I don't care how strong your 12v rail is if the PSU can't meet the needed wattage. Just some food for thought..

i might go for an 850 Watt psu since 1000 is really an overkill but future proof i suppose.

i've heard two lightnings heavy overclocked pull alot of wattage out of you're psu, might go to the 750ish. is that true?
i'll overclock them with the "hacked" bios.

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I don't know.. Nvidia doesn't certify the tx850 psu to sli 2x GTX580's.. They haven't updated there list as of yet with the GT6XX series.. here it is.. Like I said the lighting is already overclocked and your going to overclock it more.. Then I'd want to feed as much clean power to those cards as possible. That's why I said the 1050w PSU. You can try a TX850, but if I was going all out GPU wise.. I'd do the same with the PSU.

True, there are some high watt PSU's out there with shitty multi 12v rails. I have a lot of CX430 psu's in my crunching farm purely due to the fact it has a strong single 12v rail. But.. I believe I would follow the min requirements of the manufacture to not void my warranty. and I don't care how strong your 12v rail is if the PSU can't meet the needed wattage. Just some food for thought..

I don't know.. Nvidia doesn't certify the tx850 psu to sli 2x GTX580's.. They haven't updated there list as of yet with the GT6XX series.. here it is.. Like I said the lighting is already overclocked and your going to overclock it more.. Then I'd want to feed as much clean power to those cards as possible. That's why I said the 1050w PSU. You can try a TX850, but if I was going all out GPU wise.. I'd do the same with the PSU.

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" It was a bit of a shocker, went to try with 2600k at 4.5Ghz, 2 x 680L at 1400/1752, +100mV. Got a full rig shutdown in gt1, 1080W showing on the meter. Tried cards completely stock volts & clocks (ln2 bios), pulls 756w from the wall.
OCed +100 on the core & +499 mem (1307/1752), no added volts, 820w from the wall. Added 50mV with same clock, 900w from the wall.
Only extras attached to the mobo are 2 case fans & 1 ssd. Cooling is externally powered." so he's basicly saying it pulled 900w from the wall ( overclocked ) 1000+
they are so expensive the 1000W series.. arent the platiniums good ones?

they overclock very well and are different beasts when theyre at max overclock.

" It was a bit of a shocker, went to try with 2600k at 4.5Ghz, 2 x 680L at 1400/1752, +100mV. Got a full rig shutdown in gt1, 1080W showing on the meter. Tried cards completely stock volts & clocks (ln2 bios), pulls 756w from the wall.
OCed +100 on the core & +499 mem (1307/1752), no added volts, 820w from the wall. Added 50mV with same clock, 900w from the wall.
Only extras attached to the mobo are 2 case fans & 1 ssd. Cooling is externally powered." so he's basicly saying it pulled 900w from the wall ( overclocked ) 1000+
they are so expensive the 1000W series.. arent the platiniums good ones?

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80 Plus (Bronze, Silver, Gold, Platinum, and Titanium) is just the efficiency level. The higher the level the better power efficiency and reducing electricity usage. So, 80 Plus platinium PSU would be better at power efficiency than a 80 Plus Gold. But the price really goes up with those levels..

EDIT: Those expensive 1000w series are expensive, but about half the price of one of your GTX680's..

True, there are some high watt PSU's out there with shitty multi 12v rails. I have a lot of CX430 psu's in my crunching farm purely due to the fact it has a strong single 12v rail. But.. I believe I would follow the min requirements of the manufacture to not void my warranty. and I don't care how strong your 12v rail is if the PSU can't meet the needed wattage. Just some food for thought..

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Wattage(power) is amp x volts. So the amount of watts is dependent on amps since the PSU will hold the voltage at 12. Some manufacturers underrates their PSU to be safe. The CX430 v1 has a 27A 12V but the CX430 v2 has a 33A 12V rail. They did not change the rating even though the PSU can actually produce more than 430W. Some review sites will push PSU past their rated wattage to see what the real max output is.
Do I recommend you to go past the rated power? absolutely not but underrating and overrating in the industry is normal. A trusted brand like Corsair will most likely not cheat you. However, I think if you are going to build or upgrade parts on your own then you should at least do some research and learn the basics.

I also can't see how they can void your warranty as they don't really know what your psu is. They surely will not visit your home to check it. It will come down to you telling them and you can tell them whatever you want.

Wattage(power) is amp x volts. So the amount of watts is dependent on amps since the PSU will hold the voltage at 12. Some manufacturers underrates their PSU to be safe. The CX430 v1 has a 27A 12V but the CX430 v2 has a 33A 12V rail. They did not change the rating even though the PSU can actually produce more than 430W. Some review sites will push PSU past their rated wattage to see what the real max output is.
Do I recommend you to go past the rated power? absolutely not but underrating and overrating in the industry is normal. A trusted brand like Corsair will most likely not cheat you. However, I think if you are going to build or upgrade parts on your own then you should at least do some research and learn the basics.

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I don't understand why you even felt the need to post this information. Little research is needed to listen to the minimum required wattage(power) when the manufacturer tells you. I think if you are going to offer advice that no one is asking, then you should create a new thread. The OP doesn't need a 430w PSU. and he doesn't need to test the power supplying barriers of his under rated PSU either.

I don't understand why you even felt the need to post this information. Little research is needed to listen to the minimum required wattage(power) when the manufacturer tells you. I think if you are going to offer advice that no one is asking, then you should create a new thread. The OP doesn't need a 430w PSU. and he doesn't need to test the power supplying barriers of his under rated PSU either.

Please stick to helping the OP or move along. Last warning.

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I referenced the CX430 as an example of power ratings and how it can be misleading.

You said "I don't care how strong your 12v rail is if the PSU can't meet the needed wattage"
When you say strong I would assume amps because it can't mean anything else. You don't care how "strong" it is? amps directly affect wattage. It doesn't matter what marketing says it's rated as when you can the real spec of the PSU.

If for some reason Corsair decides to bump the 12V line to 60 amps and still rate it at 430W then it will run both his 680.

I even calculated his wattage a few posts up.

The whole point is to look at the actual product spec and know what you need rather than just going out and buying a 850w or 1000 watt product. There are some really bad 850W psu out there.

" It was a bit of a shocker, went to try with 2600k at 4.5Ghz, 2 x 680L at 1400/1752, +100mV. Got a full rig shutdown in gt1, 1080W showing on the meter. Tried cards completely stock volts & clocks (ln2 bios), pulls 756w from the wall.
OCed +100 on the core & +499 mem (1307/1752), no added volts, 820w from the wall. Added 50mV with same clock, 900w from the wall.
Only extras attached to the mobo are 2 case fans & 1 ssd. Cooling is externally powered." so he's basicly saying it pulled 900w from the wall ( overclocked ) 1000+
they are so expensive the 1000W series.. arent the platiniums good ones?

they overclock very well and are different beasts when theyre at max overclock.

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Yea, the numbers really goes up when you add overclocking to the mix. I wish someone here with SLi GTX680's would jump in and suggest the best PSU. From what you have posted a 1050w PSU may not be enough for the best overclock. The AX1200 or AX1200i maybe something else you might want to think about as well. Those PSU's are high, but still only a quarter of the cost of your GPU's.

Yea, the numbers really goes up when you add overclocking to the mix. I wish someone here with SLi GTX680's would jump in and suggest the best PSU. From what you have posted a 1050w PSU may not be enough for the best overclock. The AX1200 or AX1200i maybe something else you might want to think about as well. Those PSU's are high, but still only a quarter of the cost of your GPU's.

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its pretty insane with how the Wattage increases... with more overclocking or to the max.
i mean , ofcourse i will overclock them.. you know if i have the oc room why not?
they overclock very good.
there is a thread in Overclock.net ( Lightning owners i might find my answer there )

It was a bit of a shocker, went to try with 2600k at 4.5Ghz, 2 x 680L at 1400/1752, 100mV. Got a full rig shutdown in gt1, 1080W showing on the meter. Tried cards completely stock volts & clocks (ln2 bios), pulls 756w from the wall.
OCed 100 on the core & 499 mem (1307/1752), no added volts, 820w from the wall. Added 50mV with same clock, 900w from the wall.
Only extras attached to the mobo are 2 case fans & 1 ssd. Cooling is externally powered." so he's basicly saying it pulled 900w from the wall ( overclocked ) 1000
they are so expensive the 1000W series.. arent the platiniums good ones?

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This doesn't make a lot of sense to me. My 550/650 platinum/gold psu (yes it's a little odd) doesn't seem to have a problem running my 660 Tis unclocked and maxed out with the same cpu and overclock. The 680 doesn't look that much more power hungry going by the charts.

Yea, the numbers really goes up when you add overclocking to the mix. I wish someone here with SLi GTX680's would jump in and suggest the best PSU. From what you have posted a 1050w PSU may not be enough for the best overclock. The AX1200 or AX1200i maybe something else you might want to think about as well. Those PSU's are high, but still only a quarter of the cost of your GPU's.

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2 x 7970's and a core i7 3770K at 4.7GHz and the 7970's at 1200/1600 overvolted draw about 720 watts at full load...... 680's draw less thus a good quality 750Watt PSU will easily do thew trick. Now your asking someone in to chime in on recommendations and your blindly suggesting a 850 watt. Just saying.... I have no Idea where 1050 watt is coming in for 2 x 680's?????? I guess we could keep throwing blind suggestions against the wall....

For a system using two GeForce GTX 680 graphics cards in 2-way SLI mode NVIDIA specifies a minimum of a 750 Watt or greater power supply that has a combined +12 Volt continuous current rating of 53 Amps or greater and that has at least four 6-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Total Continuous Amperage Available on the +12V Rail(s) is the most important factor.